упростить выражение 1- 1/cos^2a

упростить выражение 1- 1/cos^2a
- Предмет:
  Алгебра
- Автор:
  olivia22
- 7 лет назад

Ответы 2

1 - 1/cos²a =Приводим в общему знаменателю:(cos²a -1)/ cos²a =___________________Основное тригонометрическое тождество:sin²a + cos²a = 1- sin²a = cos²a -1_________________-sin²a/ cos²a= - tg²aОтвет: -tg²a
- Автор:
  elisaboyer
- 7 лет назад
- 0
1 - 1/cos^2a = (cos^2a-1)/cos^2a= -sin^2a/cos^2a= -tg^2a

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- Автор:
  leiae9dh
- 7 лет назад
- 0
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